A new device for rapid evaluation of biofilm formation potential by bacteria.

This work describes the implementation of a new assay named the BioFilm Ring Test to evaluate the ability of bacteria to form biofilms. This assay is based on the immobilisation (or not) of magnetic beads embedded by bacterial aggregates or mats (patented concept). It is realised on modified polystyrene 96-wells microtiter plates with individual 8-wells slides.

Proteolytic activity in Encephalitozoon cuniculi sporogonial stages: predominance of metallopeptidases including an aminopeptidase-P-like enzyme.

A fraction enriched in spore precursor cells (sporoblasts) of the microsporidian Encephalitozoon cuniculi, an intracellular parasite of mammals, was obtained by Percoll gradient centrifugation. Soluble extracts of these cells exhibited proteolytic activity towards azocasein, with an alkaline optimum pH range (9-10). Prevalence of some metallopeptidases was supported by the stimulating effect of Ca2+, Mg2+, Mn2+ and Zn2+ ions, and inhibition by two chelating agents (EDTA and 1,10-phenanthroline), a thiol reductant (dithiothreitol) and two aminopeptidase inhibitors (bestatin and apstatin).

Two-dimensional electrophoresis database of Listeria monocytogenes EGDe proteome and proteomic analysis of mid-log and stationary growth phase cells.

Listeria monocytogenes is the causative agent of listeriosis, one of the most significant foodborne diseases in industrialized countries. The complete genome of the L. monocytogenes EGDe strain, belonging to the serogroup 1/2a, has been sequenced and is comprised of 2853 open reading frames.

Antimicrobial effects of sanitizers against planktonic and sessile Listeria monocytogenes cells according to the growth phase.

This study was designed to investigate the individual or combined effects of sanitizers on survival of planktonic or sessile Listeria monocytogenes cells at different phase of growth. The sanitizers tested included: (i) acetic acid (pH 5.0), (ii) NaOH (pH 12.

Listeria monocytogenes LO28: surface physicochemical properties and ability to form biofilms at different temperatures and growth phases.

The surface physicochemical properties of Listeria monocytogenes LO28 under different conditions (temperature and growth phase) were determined by use of microelectrophoresis and microbial adhesion to solvents. The effect of these parameters on adhesion and biofilm formation by L. monocytogenes LO28 on hydrophilic (stainless steel) and hydrophobic (polytetrafluoroethylene [PTFE]) surfaces was assessed.